similar to: [LLVMdev] Source code annotations on loops

hi, On Fri, May 7, 2010 at 8:59 AM, Trevor Harmon <Trevor.W.Harmon at nasa.gov>wrote: > Hi, > > For me, getTripCount always returns null, even for trivial loops such > as: > > void simple(int j) { > for (int i = 0; i < 10; i++) { > j++; > } > } > > Looking through the mailing list archive, it appears that getTripCount > requires

Hi, For me, getTripCount always returns null, even for trivial loops such as: void simple(int j) { for (int i = 0; i < 10; i++) { j++; } } Looking through the mailing list archive, it appears that getTripCount requires certain optimization passes to run first, but it's not clear which ones. There doesn't seem to be any documentation on this. Does anybody

On May 6, 2010, at 6:32 PM, ether zhhb wrote: > As the comment said: > /// The IndVarSimplify pass transforms loops to have a form that > this > /// function easily understands. > > you could try -indvars. After adding -indvars to the opt command, getTripCount still returns null. I suppose it's possible, depending on the scheduling of the pass manager, that

On May 7, 2010, at 11:17 AM, Trevor Harmon wrote: > On May 6, 2010, at 6:32 PM, ether zhhb wrote: > >> As the comment said: >> /// The IndVarSimplify pass transforms loops to have a form that >> this >> /// function easily understands. >> >> you could try -indvars. > > After adding -indvars to the opt command, getTripCount still returns

On Feb 9, 2010, at 11:13 AM, Trevor Harmon wrote: > Is there any information about these changes and why they were > necessary? I think I found it: http://nondot.org/~sabre/LLVMNotes/EmbeddedMetadata.txt Still looking for an API to access the metadata... Trevor

On Feb 8, 2010, at 8:51 PM, Duncan Sands wrote: > this can be done using debug info. Check out > http://llvm.org/docs/SourceLevelDebugging.html Wow, that threw me for a loop. I'm using the 2.6 release, thinking I was up to date, but its debug output doesn't look anything like what's described in the above link. It appears to document the upcoming 2.7 version, which

On 16 February 2010 20:49, Trevor Harmon <Trevor.W.Harmon at nasa.gov> wrote: > We were discussing that a few days ago: > > http://lists.cs.uiuc.edu/pipermail/llvmdev/2010-February/029245.html Hi Trevor, On a similar question, I'd want to see what line is being compiled to which instructions. Is it possible to print the before the instructions as comment? For example:

Trevor Harmon <Trevor.W.Harmon at nasa.gov> writes: [snip] > Could someone > please explain why I should use dyn_cast instead of dynamic_cast? (I > thought all classes have v-tables...) Thanks, For reducing executable size, LLVM builds with RTTI disabled where possible.

On Feb 25, 2010, at 2:28 PM, Trevor Harmon wrote: > I'm not sure how the other program can find the output, unless > of course the analyzer simply dumps the file to a hard-coded > location (/tmp?). Replying to myself again... After sifting through many of the existing transforms, I discovered that new command-line parameters can be added to opt simply by declaring them in the

On Wed, Mar 31, 2010 at 2:59 PM, Trevor Harmon <trevor.w.harmon at nasa.gov> wrote: > I'm wondering what would cause a CFG not to have a return block. The > comments in UnifyFunctionExitNodes.cpp say: "If there are no return > stmts in the Function, a null pointer is returned." But this doesn't > make sense; even an empty void function has a return block with a

On Wed, Feb 17, 2010 at 3:07 AM, Renato Golin <rengolin at systemcall.org> wrote: > On 16 February 2010 20:49, Trevor Harmon <Trevor.W.Harmon at nasa.gov> wrote: >> We were discussing that a few days ago: >> >> http://lists.cs.uiuc.edu/pipermail/llvmdev/2010-February/029245.html > > Hi Trevor, > > On a similar question, I'd want to see what line is

On May 10, 2010, at 11:45 AM, Dan Gohman wrote: > just make your front-ends add -indvars before > adding your pass. Sorry, I don't have a clue how to do this, and I can't find any docs about it. I'm using llvm-gcc; how can I tell it to add a pass? Trevor

On Feb 25, 2010, at 11:16 AM, Trevor Harmon wrote: > Is there perhaps some structured mechanism for retrieving the output > of an LLVM pass? That is, something better than just parsing the > output of "opt"... On rereading the opt documentation, I see: "In a few cases, it will ... generate a file with the analysis output, which is usually done when the output is meant

LLVM has a relatively large number of proprietary replacements for standard C++ functions and classes. One of these is dyn_cast to replace dynamic_cast. The two calls appear to be semantically equivalent; the only difference that I can see is that dyn_cast reportedly works on classes that have no v-table [1]. Could someone please explain why I should use dyn_cast instead of dynamic_cast?

On Feb 13, 2010, at 7:22 AM, Jingyue Wu wrote: > I would like to know how to locate an LLVM instruction in the source > code, i.e. to get the line number of its corresponding source code > statement. I remember in LLVM 2.4, DbgStopPointInst is designed to > help this locating, but it seems deprecated in the latest LLVM. We were discussing that a few days ago:

On Mar 30, 2010, at 7:51 PM, John Criswell wrote: > I'm too lazy to convert your .dot file into a graph file What format should I have posted? (I'm not sure what you mean by "graph file".) I had thought that .dot was the preferred format here, since that's what LLVM generates (e.g., "opt -dot-cfg ..."). > First, LLVM does not guarantee that a function

On Thursday 25 February 2010 17:30:24 Trevor Harmon wrote: > On Feb 25, 2010, at 2:28 PM, Trevor Harmon wrote: > > I'm not sure how the other program can find the output, unless > > of course the analyzer simply dumps the file to a hard-coded > > location (/tmp?). > > Replying to myself again... > > After sifting through many of the existing transforms, I

-----Original Message----- From: Trevor Harmon <Trevor.W.Harmon at nasa.gov> Sent: Tuesday, July 13, 2010 4:46 PM To: Duncan Sands <baldrick at free.fr> Cc: llvmdev at cs.uiuc.edu <llvmdev at cs.uiuc.edu> Subject: Re: [LLVMdev] CallGraphSCCPass: symbol not found > On Jul 12, 2010, at 11:37 PM, Duncan Sands wrote: > > > $ c++filt _ZTIN4llvm16CallGraphSCCPassE >

On Mon, May 10, 2010 at 8:05 PM, Trevor Harmon <Trevor.W.Harmon at nasa.gov> wrote: > On May 10, 2010, at 8:43 AM, Xinfinity wrote: > >> Is it possible to get the list of BasicBlocks building the condition >> of a loop and the list of BasicBlocks that form the body? > > Based on my (limited) experience with Loop and LoopInfo, this isn't > possible. (But

In your example the the number of iterations is known -- it is N. It is not known at compile time, but it's known at run-time before you enter the loop. So you can do transforms like if( N < threshold ) copy of loop optimized for small iterations count; else copy of loop optimized for large iterations count; But you are right, in general, the number of iterations in unknown. I think Khaled